html, body { margin: 0; height: 100%; font-family: "PingFang SC", "Microsoft YaHei", Arial, sans-serif; }
#app { display: flex; flex-direction: column; height: 100vh; }
#header { padding: 10px 14px; font-weight: 600; background: #1F4E79; color: #fff; }
#chat { flex: 1; overflow-y: auto; padding: 12px; background: #F7F8FA; }
.msg { margin-bottom: 10px; max-width: 85%; padding: 8px 12px; border-radius: 8px; line-height: 1.5; font-size: 14px; white-space: pre-wrap; }
.msg.user { margin-left: auto; background: #DCE6F5; }
.msg.ai { margin-right: auto; background: #fff; border: 1px solid #E0E0E0; }
#inputBar { display: flex; padding: 10px; border-top: 1px solid #E0E0E0; background: #fff; }
#question { flex: 1; padding: 8px 10px; border: 1px solid #CCC; border-radius: 6px; font-size: 14px; }
#send { margin-left: 8px; padding: 8px 16px; border: none; border-radius: 6px; background: #2E75B6; color: #fff; cursor: pointer; }
#send:disabled { background: #A9C4DC; cursor: not-allowed; }
#status { font-size: 12px; color: #888; padding: 4px 12px; }